Windows 8 BluRay Software?

Just upgraded to Windows 8 and loving it but my LG BluRay writer came bundled with Cyberlink Power DVD9 which was great with Win 7 for BluRay viewing on the PC. Sadly it's not supported in Windows 8 and the new version is Power DVD12 which costs $49 to upgrade! I have tried VLC's latest version and although it claims BluRay support it is crashing after just 2 seconds opening a BluRay disc.

I'm confused as to why programs, or even drivers, won't work in Windows 8, if they worked happily in Windows 7?
I thought they were basically the same under the hood, apart from the Metro bit?

Perhaps I was just lucky when I upgraded, but all my programs and drivers work in 8 just the same as they did in 7. Even old XP programs.

(I realise this is of no help to the OP sorry )

A small change could require a large change under the hood and generally most companies won't rewrite drivers for stuff thats no longer for general sale and MS will also change how things work with each version of the OS so a program that expects a certain response from a Win 7 system may freak out when it gets the same thing from a Win 8 machine at a low level